Use a variable in a function

Just add b as a parameter of the function, if I understand you correctly.

Consider:

def function(user,b):
    user.getApple().eatTheApple(b, 2000, 50, 1, 8663, 4444)

Then we could test with (assuming the class User is defined somewhere else):

import random
myUser = User()

b = random.choice([2309,1897,2307])
function( myUser , b )

We've made a function of two parameters, and passed them both in! An alternative would be:

def function(user):
    user.getApple().eatTheApple( random.choice([2309,1897,2307], 2000, 50, 1, 8663, 4444)

I've assumed that User is a class somewhere, so there might be a prettier way to do this yet, if this is appropriate for your circumstances (it might not be). We have our class declaration:

class User:
    def __init__( self ):
        #this code is executed when the class is created
        self.b = random.choice([2309,1897,2307])

    def function( self ):
        #this code is owned by each User object
        user.getApple().eatTheApple(self.b, 2000, 50, 1, 8663, 4444)

That would be executed by:

myUser = User()
myUser.function()

Python likes object-oriented design, so this would be nice! However, it assumes that the "b" value is personal to the user, and doesn't change. I'll give you alternatives, if it does